Known in the art is an intrauterine device (U.S. Pat. No. 4,198,966), comprising a strip, a rod connected to the strip to form a T-shaped element, a copper coil mounted onto the rod, and a thread fixed at the rod end and adapted for dynamic monitoring.
Another prior-art intrauterine device Nova T Cu 200 Ag (Huhtamaki Co., Leiras, Finland) is known comprising a strip, a rod connected to the strip to form a T-shaped element, a copper-wire coil with a silver base, mounted onto the rod, and a thread for dynamic monitoring of the IUD in the uterine cavity, fixed at the rod end.
The aforementioned known devices are characterized by the fact that the dynamic monitoring thread fixed at the rod end through a double knot and hanging over the cervical canal, causes irritation of the uterine portion located above the cervix and, hence, contraction of the uterine muscles and expulsion of the device from the uterus.